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diff --git a/frontend-old/node_modules/web-vitals/src/attribution/onCLS.ts b/frontend-old/node_modules/web-vitals/src/attribution/onCLS.ts
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+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import {getLoadState} from '../lib/getLoadState.js';
+import {getSelector} from '../lib/getSelector.js';
+import {onCLS as unattributedOnCLS} from '../onCLS.js';
+import {
+  CLSAttribution,
+  CLSMetric,
+  CLSMetricWithAttribution,
+  ReportOpts,
+} from '../types.js';
+
+const getLargestLayoutShiftEntry = (entries: LayoutShift[]) => {
+  return entries.reduce((a, b) => (a && a.value > b.value ? a : b));
+};
+
+const getLargestLayoutShiftSource = (sources: LayoutShiftAttribution[]) => {
+  return sources.find((s) => s.node && s.node.nodeType === 1) || sources[0];
+};
+
+const attributeCLS = (metric: CLSMetric): CLSMetricWithAttribution => {
+  // Use an empty object if no other attribution has been set.
+  let attribution: CLSAttribution = {};
+
+  if (metric.entries.length) {
+    const largestEntry = getLargestLayoutShiftEntry(metric.entries);
+    if (largestEntry && largestEntry.sources && largestEntry.sources.length) {
+      const largestSource = getLargestLayoutShiftSource(largestEntry.sources);
+      if (largestSource) {
+        attribution = {
+          largestShiftTarget: getSelector(largestSource.node),
+          largestShiftTime: largestEntry.startTime,
+          largestShiftValue: largestEntry.value,
+          largestShiftSource: largestSource,
+          largestShiftEntry: largestEntry,
+          loadState: getLoadState(largestEntry.startTime),
+        };
+      }
+    }
+  }
+
+  // Use Object.assign to set property to keep tsc happy.
+  const metricWithAttribution: CLSMetricWithAttribution = Object.assign(
+    metric,
+    {attribution},
+  );
+  return metricWithAttribution;
+};
+
+/**
+ * Calculates the [CLS](https://web.dev/articles/cls) value for the current page and
+ * calls the `callback` function once the value is ready to be reported, along
+ * with all `layout-shift` performance entries that were used in the metric
+ * value calculation. The reported value is a `double` (corresponding to a
+ * [layout shift score](https://web.dev/articles/cls#layout_shift_score)).
+ *
+ * If the `reportAllChanges` configuration option is set to `true`, the
+ * `callback` function will be called as soon as the value is initially
+ * determined as well as any time the value changes throughout the page
+ * lifespan.
+ *
+ * _**Important:** CLS should be continually monitored for changes throughout
+ * the entire lifespan of a page—including if the user returns to the page after
+ * it's been hidden/backgrounded. However, since browsers often [will not fire
+ * additional callbacks once the user has backgrounded a
+ * page](https://developer.chrome.com/blog/page-lifecycle-api/#advice-hidden),
+ * `callback` is always called when the page's visibility state changes to
+ * hidden. As a result, the `callback` function might be called multiple times
+ * during the same page load._
+ */
+export const onCLS = (
+  onReport: (metric: CLSMetricWithAttribution) => void,
+  opts?: ReportOpts,
+) => {
+  unattributedOnCLS((metric: CLSMetric) => {
+    const metricWithAttribution = attributeCLS(metric);
+    onReport(metricWithAttribution);
+  }, opts);
+};